Today Light Emitting Diodes are often used in lighting assemblies or lamps. One Light Emitting Diode (LED) often lacks enough light output to form a lamp that replaces well-known incandescent lamps, halogen lamps or gas discharge lamps even if high lumen Light Emitting Diodes are used. Therefore, in several lighting assemblies, several Light Emitting Diodes are combined into one assembly to increase the total light intensity that may be emitted by the assembly. A known way of combining several Light Emitting Diodes is to assemble them in an array-like configuration on a printed circuit board. The printed circuit board is an example of a substrate on which the Light Emitting Diodes can be provided. The printed circuit board may be build up by combining several layers of metal and electrical isolators such that heat can be transported away from the Light Emitting Diodes—each Light Emitting Diode must be cooled because it generates a relatively large amount of heat in a relatively small volume. A disadvantage of arranging the Light Emitting Diodes in an array-like configuration on a substrate is that each Light Emitting Diode has, seen in two perpendicular directions along the substrate, 4 to 8 neighbor Light Emitting Diodes. The heat generated by each one of the Light Emitting Diodes is spread into a direction along the substrate and, thus, heat generated by a Light Emitting Diode is distributed towards its neighbor Light Emitting Diodes. Thus, the Light Emitting Diodes heat each other up. If Light Emitting Diodes become too warm, their efficiency decreases and their lifetime is reduced significantly.
The above discussed example of a lighting assembly has also another disadvantage. For example, when quite a large number of Light Emitting Diodes must be integrated into a single assembly, the area of the substrate becomes relative large and thereby the assembly is not compact anymore.